p1-0x.cpp 2.1 KB

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  1. // RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
  2. // The result of the expression const_cast<T>(v) is of type T. If T is
  3. // an lvalue reference to object type, the result is an lvalue; if T
  4. // is an rvalue reference to object type, the result is an xvalue;.
  5. unsigned int f(int);
  6. struct X {};
  7. template<typename T> T& lvalue();
  8. template<typename T> T&& xvalue();
  9. template<typename T> T prvalue();
  10. void test_classification(const int *ptr, X x) {
  11. int *&&ptr0 = const_cast<int *&&>(ptr);
  12. int *&&ptr1 = const_cast<int *&&>(xvalue<const int*>());
  13. int *&&ptr2 = const_cast<int *&&>(prvalue<const int*>()); // expected-error {{const_cast from rvalue to reference type 'int *&&'}}
  14. X &&ptr3 = const_cast<X&&>(x);
  15. X &&ptr4 = const_cast<X&&>(xvalue<X>());
  16. X &&ptr5 = const_cast<X&&>(prvalue<X>());
  17. int *&ptr6 = const_cast<int *&>(ptr);
  18. int *&ptr7 = const_cast<int *&>(xvalue<const int*>()); // expected-error {{const_cast from rvalue to reference type 'int *&'}}
  19. int *&ptr8 = const_cast<int *&>(prvalue<const int*>()); // expected-error {{const_cast from rvalue to reference type 'int *&'}}
  20. X &ptr9 = const_cast<X&>(x);
  21. X &ptrA = const_cast<X&>(xvalue<X>()); // expected-error {{const_cast from rvalue to reference type 'X &'}}
  22. X &ptrB = const_cast<X&>(prvalue<X>()); // expected-error {{const_cast from rvalue to reference type 'X &'}}
  23. }
  24. struct A {
  25. volatile unsigned ubf : 4;
  26. volatile unsigned uv;
  27. volatile int sv;
  28. void foo();
  29. bool pred();
  30. };
  31. void test(A &a) {
  32. unsigned &t0 = const_cast<unsigned&>(a.ubf); // expected-error {{const_cast from bit-field lvalue to reference type}}
  33. unsigned &t1 = const_cast<unsigned&>(a.foo(), a.ubf); // expected-error {{const_cast from bit-field lvalue to reference type}}
  34. unsigned &t2 = const_cast<unsigned&>(a.pred() ? a.ubf : a.ubf); // expected-error {{const_cast from bit-field lvalue to reference type}}
  35. unsigned &t3 = const_cast<unsigned&>(a.pred() ? a.ubf : a.uv); // expected-error {{const_cast from bit-field lvalue to reference type}}
  36. unsigned &t4 = const_cast<unsigned&>(a.pred() ? a.ubf : a.sv); // expected-error {{const_cast from rvalue to reference type}}
  37. }